Monoazo dyestuffs



Patented Oct. 2, 1951 and Willy Widmer, Bot assignors to CibagLimited,

a Swiss firm tmingen, Switzerland, Basel, Switzerland,

No Drawing. Application February 18, 1947, Se-

iigal No. 729,417. In Switzerland February 27,

13 Claims.

According to this invention valuable new dye- ,stufis capable of being chromed are made by treating an ortho ortho'-dihydroxy-monoazordyestuff, which contains a single sulfonic acid group, with an organic acylating agent.

The expression ortho ortho dihydroxymonoazo-dyestuifs is used herein to denote monoazo-dyestuffs containing the atomic groupin to an HO-group, and so selecting the two starting components that one of them contains a sulfonic acid group. The ortho-amino-hydroxybenzenes or ortho-amino-hydroxynaphthalenes to be converted into diazo-compounds may contain further substituents, for example, the above mentioned sulfonic acid group, and also other substituents. As such substituents there may be mentioned, for example, halogen atoms such as bromine and especially chlorine, nitro groups,

.allzoxy groups, sulfonic acid alkylaryl-amide I groups or alkyl groups.

As examples of such ortho-aminmhydroxy-compounds to be converted into the diazo compound there may be mentioned the following:

Components containing a sulfonic acid group which are to be coupled with azo-components free from sulfonic acid groups, namely Z-amino- 1shydroxybenzenee lasulfonic acid, 4-methyl-2- amino 1 hydroxybenzene-S-sulfonic acid, 4- chloro 2 amino 1-hydroxybenzene-6sulfonic acid, 4-nitro-2-amino-hydroxybenzene-6-su1fonic acid, 6 nitro-Z-amino-l-hydroxybenzenel-sulfonic acid, 5-nitro- 2-amino-l-hydroxybenzenelsulfonic acid, l-amino-2-hydroxy-naphthalene- 4-sulfonic acid, Z-amino 1 hydroxy-naphthalene--sulfonic acid or 6 nitro-l-amino-Z-hydroxy-naphthalene-4-sulfonic acid; components free i'rom'sulfonic acidgroups which are to be coupled with azo-components containing a sulfonic acid group, namely Z-amino-l-hydroxybenzene, 4-chloro-2-amino 1 hydroxybenzene, 4 6-dichloro-2-amino-1-hydroxybenzene, 3 4 6- trichloro-Z-amino-l-hydroxybenzene, 6-nitro-4- methyl-Z-amino 1 hydroxybenzene, 4-nitro-2- amino-l-hydroxybenzene, 5-nitro-2-amino-1-hydroxybenzene, G-nitro 2 amino-l-hydroxybenzene, 5-nitro-4-chloro-2-amino 1 hydroxybenzene, 6-nitro-2-amino-4-chloro 1 hydroxybens zene, 4-.-nitro-6-chloro-2-amino 1 hydroxybenzene, 4:6-dinitro-2-amino-l-hydroxybenzene or 2-amino-1-hydroxybenzene--sulfonic acid diethylamide.

As azo-components which come into consideration for making the starting materials used in the present process there are suitable those which owe their couplingrcapacity to a phenolic hydroxyl group or to the presence of a reactive methylene group. As examples of such azo-components there may be mentioned: Y

Hydroxypyrene, hydroxybenzenes capable of coupling in ortho-position with respect to the hydroxyl group, such as '1-hydroxy-4-methylbenzene, 1-hydroxy-4-tertiary amyl-benzene, 1- hydroxy-4-isobuty1-benzene; 8-hydroxy quinclines capable of coupling in ortho-position with respect to the hy'droxyl group, such as 5-chloro- S-hydroxy-quinoline; acetoacetic acid arylides such as acetoacetic acid anilide or acetoacetic acid 'ortho-anisidide; and also 2:4-dihydroxyquinoline and the like. Especially good results can be obtained with hydroxynaphthalenes which couple in ortho-position with respect to a hydroxyl group or are capable of coupling in such a position, or with Dyrazolones, especially l-aryl (for example, phenyl) 3-methyl-5-pyrazolones.

As examples of such azo-components there may be mentioned: 1 hydroxy naphthalene (in which case it is necessary to work under conditions such that coupling occurs in the 2-position, for example, in a medium rendered strongly alkaline with caustic alkali), 5-chloro-1-hydroxynaphthalene, 5:8-dichloro 1 rhydroxynaphthalene, l-hydroxy 4 methoxynaphthalene, 2-hydroxy-naphthalene, 2-hydroxy-6-methoxynaphthalene, 2-hydroxy-7-methoxynaphthalene, 2-hydroxy-naphthalene-fi-su1fonic acid diethylamide, l-hydroxy naphthalene 4 sulfonic acid, l-hydroxynaphthalene' 5 sulfonic acid, 2-hydroxynaphthalenel-sulf-onic acid, 2-hydroxynaphthalene 6 sulfonic acid, Z-hydroxynaphthalene-"lsulfonic acid, 1-hydroxynaphthalene-3-sulfonic acid-N-methylanilideell-sulfonic acid; 3- -methyl -pyrazolone, 1 3-diphenyl-5-pyrazolone, l-phenyl-3-methyl-5-pyrazolone, 1- (3'-nitro) -phenyl-3- methyl-5-pyrazolone, 1 (2' chloro) phenyl-3- methyl 5 pyrazolone, 1 (3' sulfo) -phenyl-3- methyl-5-pyrazolone, 1 (2 chloro 5' sulfo) phenyl-3-methyl-5-pyrazolone, 1-(2'-methyl-5'- sulfo) -phenyl-3-methyl-5-pyrazolone.

As acylating agents for use in treating the ortho ortho-dihydroxy-monoazo-dyestufis containing a sulfonic acid group in accordance with the invention there may be mentioned acylating' monium sulfate.

fa'mmonium sulfate is known under the name agents which contain as the sole acylating group a functionally converted carboxyl group, for example, carboxylic acid halides such as the acid bromides or chlorides, or carboxylic 'anhydrides.

Among these compounds especially good results can be obtained with those which are free from groups imparting solubility and substituents convertible into such groups, for example, cinnamic acid chloride, arylhydroxyacetic acid halides, acetic anhydride, butyric acid chloride, and the like, and above all derivatives of benzoic' acid such asmetaor para-nitrobenzoyl chloride and principally benzoic acid halides such as benzoyl bromide and especially benzoyl chloride.

The treatment with the acylating agent may 'with advantage be carried out in the presence of 'a tertiary organic' base, for example pyridine. 'It'is also generally desirable to work in an anhydrous'medium and in the absence "of free alkalies. In the case of dyestuffs which have been obtained by coupling a diazotized ortho-aminoh'ydro'xybenzene or ortho-amino-hydroxynaph-- 'thalene with a compound coupling in ortho-positionwith respect to a phenolic hydroxyl group, for example, with a hydroxynaphthalene, the acylation may be carried out differently. However, it must be carried out in such a manner that at least one hydroxyl group in ortho-position with respect to the azo-group is acylated. The second hydroxyl group in ortho-position with respect to the azo-group may then remain unchanged depending on the kind and quantity of the acylating agent and on the conditions of the reaction, or it may be acylated in part of the dyestuff subjected to the acylation, or be acylated entirely. In the case of dyestuffs which are obtained by using 1-phenyl-3-methyl-5-pyrazolones as coupling components the enolized keto group in the 5-position of the pyrazolone residue is not .easily esterified by the present process.

The monoazo-dyestufifs obtainable by the present process are new and correspond to the for- .mula 0-.

I N=N-I z in which the groups -O-- are in positions adjajcent to the -N=N- group, R1 represents an aromatic radical containing at the most two lcondensed rings, R2 represents a residue of a coupling component, at least one aromatic bound j -O- group is attached by its free valency to the -CO- group of a carboxylic acid which is free from substituents imparting solubility, and in which the residue .contains'a single sulfonic acid group.

The mono-azo-dyestufis obtainable by them- -vention are principally suitable for dyeing by the chroming process in which the dyeing is'carried out by the single bath process with baths (which contain the dyestuff and also an agent yielding chromium. A dyeing process oi this synchromate process or metachrome process. A special object ofthe invention is to enable chromable dyestuffs which are not suitable for dyeing by the. aforesaid single bath chroming process into'dyestufis which are especially suitable for this dyeing process. In the dyeing process the complex chromium compound of the dyestuff is formed with the elimination of the acyl residue. The dyeings so obtained'may be distinguished by very, good properties of fastness, especially by very good properties of wet fastness. As ,fibers whichmay be dyed by the single bath chroming process, especially the so-called synchromate' process, with the monoazo-dyestuffs obtainable by the invention, there may bementioned prin cipally fibers of animal origin such as silk, leather and principally wool. Mixed fabrics, for example of wool and regenerated cellulose and also animalized cellulose, artificial fibers of casein, artificial fibers of superpolyamides or superpolyurethanes, can be dyed in this manner.

As compared with the process of French Patent No. 914,640, in which is describedthe manufacture of ester-like derivatives of ortho orthodihydroxyazo-dyestuffs which are sparingly soluble to insoluble in water which are derived from dyestuffs free from sulfonic acid groups and which contain in addition to the group which brings about acylation, an atomic grouping which determines the solubility of the acylation product, the process of the present invention for producing chromable dyestufis is distinguishedby the use of ortho ortho-dihydroxyazo-dyestuffs containing a sulfonic acid group as starting ma,-- terials, and by the use advantageously as acylating agents of compounds which are free from groups impartingsolubility and substituents convertible into such groups.

The following examples illustrate theinvention; the parts being by weight: I

Example 1 tained for 2 hours at 40-45 C., and the greater part of the pyridine is then distilled under reduced pressure. The residue is stirred into about 400 parts of water, the dyestufi ester of the formula mula

is obtained when, instead of l-hydroxy-naphthalene, 2-hydroxy-naphthalene is coupled with the diazo-compound of i-aminod-hydroxynaphthalene4-sulfonic acid" to form the dyestuff to be esterified.

Example 2 112 parts of benzoyl chloride are introduced drop-Wise while thoroughly stirring in 280 parts of'dry pyridine, and then there are introduced 44 parts of the finely pulverized and thoroughly dried dyestuif' obtained by coupling diazotized -l' -amino 6 nitro 2 hydroxy-naphthalenel-sulfonic acid with 2-hydroxy-naphthalene. The temperature of the esterification mixture is maintained for 2 hours at 40- l5 C., and then the: greater part of the pyridine is distilled under reduced pressure. The residue is stirred'in about 400 parts of water, the dyestufi ester of the for- --mula is separated by filtering with suction after the addition of 20-40 parts of sodium chloride and dried under reduced pressure. 50 parts of a OzN dark red, water-soluble powder are obtained,

which dyes wool black tints by the single bath process in the presence of an agent yielding chromium.

Example 3- ion TOCQ

*isthen removed by filtering with suctionjwash ed 6 and dried. There are obtained 52 partsof a dark powder which dissolves in hot water with a bordeaux red coloration and dyes wool blue tints by the single bath process in the presence of an agent yielding chromium.

By using instead of the above-mentioned dyestuff the dyestuiT obtained by coupling diazotized 4-nitro-2-arninopheno1 with. l-hydroxynaphtha1ene-5-sulfonic acid there is obtained the dyestufi ester of the formula which is similarly soluble in hot water, and which dyes wool violet brown tints by the. single bath process in the presence of an agent yielding chromium,

V Example 4 dark red solution. The whole is stirred for 1 hour, during which the temperature is not allowed to fall below 40-45 C., about'200 parts of pyridine are then distilled under reduced pressure, andthe residue is taken up in ZOllparts of water. By the addition of 20 parts ofsodium chloride the dyestufi of the formula is completely precipitated, and then separated by filtering with suction and dried at C. under reduced pressure.

There are obtained 50 parts of an orange powder which dissolves in warm water to give a clear solution. It dyes wool pure bluish red tints by the single bath process in the presence of an agent yielding chromium.

Example 5 16.8 parts of benzoyl chloride are introduced dropwise While thoroughly stirring into 280 parts of dry pyridine at room temperature, and then there areintroduced 45.6 parts of the pulverized and dried dyestuff obtained by coupling diazo- 7 pyrazolone. The esterification is continued for '2 hours at 40-45 C., the greater part of the pyridine is then distilled under reduced pressure. :the residue is introduced into 400 parts of water, the dyestuif ester of the formula V OIN 01 rig is separated by filtering with suction, if desired, jafterthe addition of 20-40 parts of sodium chloride, and dried-under reduced pressure. About 55 parts of a red-brown water-soluble powder are obtained which dyes wool orange tints by the single bath process in the presence of an agent yielding chromium.

Example 6 -"42 parts of the dried dyestuff which has been obtained by coupling diazotized 4-nitro-2-aminophnol-G-sulfonic acid with 1-phenyl-3-methyl- 5- pyrazolone, are dissolved at 60-70 C. in 280 parts of dry pyridine, and esterified by introducing dropwise 12.5 parts of benzoyl chloride while stirring. After 1 hour the suspension is stirred in 300-400 parts of ice and the whole is rendered weakly acid to Congo by introducing ldropwise about 350 parts of hydrochloric acid "of 30 per cent. strength. The dyestufi of the formula OzN S 0311 is then separated by filtering with suction, washed with a solution of sodium chloride of percent. strength until neutraL'and dried.

The dyestufi derivative is anorange powder which dissolves to give a clear solution in warm 'water, and dyes wool reddish orange tints by the single .bath process in the presence of an agent yielding chromium.

Example 7 40 parts of the pulverized and thoroughly dried dyestuff obtained by coupling diazotized J1 hydroxy 2 amino 4 chlorobenzene 6- .sulfonic acid with 2:4-dihydroxyquinoline and washing and acidifying the product after coupling to eliminate free alkali therefrom, are .slowly esterified in 200 parts of dry pyridine while thoroughly stirring at 65-75 C. with 14 parts of ,benzoylchloride. In this manner a solution is "obtained from which the orange colored dyestuii. ester of the formula v Example 8 HO N 46 parts of the pulverized and thoroughly dried dyestuff, obtained by coupling diazotized 1- amino 2 hydroxy-naphthalene 4 sulfonic acid with 1 (2' chlyorophenyl) 3 methyl-5- pyrazolone and Washing and acidifying the product after coupling, to eliminate free alkali therefrom, are dissolved in 280 parts of dry pyridine to give a clear solution, and slowly esterified at -45 C. with 11.2 parts of benzo yl chloride while stirring. The initially clear solution becomes turbid in a short time, and the dyestuff ester partially precipitates. After stirring for 1 hour at 40-45" C. about 220 parts of pyridine are distilled under reduced pressure. The residue is stirred for a short time with 400 parts of water, 20 parts of sodium chloride are added, the'dyestufl of the formula Z is separated by filtering with suction, and dried.

55 parts of an orange-red water-soluble'powder are obtained, which dyes wool red tints by the single bath process in the presence of an agent yielding chromium. 3

Example 9 41 parts of the thoroughly dried dyestuff, obtained by coupling 'diaz'otized 4-chloro-2-aminophenol-G-sulfonic acid with 1-pheny1-3-methly- S-pyrazolone and, after coupling, acidifying the product to eliminate free alkali therefrom, are esterified in 280 parts of dry pyridine at 60-70 C. by introducing 11.2 parts of benzoyl chloride dropwise. After '1 hour the solution, in which the dyestuff ester is partially in "s an; is stirred in 300 parts of ice-water, and the whole is rendered Weakly acid to Congo, by adding dropwise about 350 parts of hydrochloric acid of 30 per cent. strength. The dyestufi ester of the formula mo-c is then then separated filtering with suction, washed neutral with cold water, and dried.

The dyestufi ester dissolves in boiling water to give a clear solution and dyes wool red tints by the single bath process in the presence of an agent yielding chromium.

' Exampze 1o 42.4 parts of the; dryMdyestuii .obtainedby O-C O CHzCHzCH;

thtQ

is completely precipitated with parts of sodium chloride, and it is then separated by filtering with suction, and dried. There are obtained parts of an orange powder, which dissolves in hot Water to give a clear solution lt; dyes wool pure bluish-red tints by the'si'rlgl'b'a'th' process in the presence of an agent yielding chromium.

Example 11 47 parts of the-dry dyestufi, obtained by coupling diazotized 1-amino 2 hydroxy-fi-nitronaphtha lenel-sulfonic acid with 1-phenyl-3-methyl 5-pyrazo1one and finally washing and acidifying the product to free it from excess alkali, are esterified. in 280 parts of dry pyridine at 65-75 C. with 12 parts of benzoyl chloride. After 1 hour the whole is diluted with about 300 parts of cold water, the pyridine neutralized with hydrolted and 'driedi *tm are to parts or an orange powder which dissolves in boiling water to give a clear solution. lt dyes wool strong yellowish red, tints by the single bath process in the presence of an agent yielding chromium.

Example i2 44 parts of the dry dyestlifi, obtained by coupling diazotized 1-hydroxy-2-aminobenzene-4- sulfonic acid' fi carbpxyli c aicl twith 1-pheny1-3- methyl-5-pyragol6ii," are ester'ified in 200 parts of dry pyridine with 11 parts of benz oyl chloride at -70 c. After 1 houi tliewhole is diluted with 300 parts of water, and the pyridine is neutralized with 235. parts. of, hydrochloric acid of. .0...ner.gentus ren th, The dyestuff ester. is. then Separ d,byafilteiins..withsuction, washed and dissolves in hot water" dried. The dyestufl ester of the formula e dred e 01s are;

presence of an and y s agent yremiug chromium;

Example 13 42 parts of the dry dyestuff, obtained by coupling diazotized 4 mtfro -Z-aminoflkhydroxybenzene-fi-sulfonic acid with 1.;phenyl-3-methyl-5- pyrazolone, are esterified in 200...parts of dry pyridine with 9.5 parts of para-nitrobenzoyl strength, the dyestufi ester of the" formula After 1 ourthe reaction mass: is taken up 300 parts of watn -neutralized wit 285 parts of hydrochloric acid of 30 per cent.

is separated by filtering with suction, washed with water, 'and'drie'd'fi There are obtained 50 parts of an orange-yellow powder which dissolves in hot water with an orange-red coloration. The dyestufi ester dyes wool orange tints by the single bath process in the presence of an agent yielding chromium.

, 7 Example. .14-

is separated by filtering, washed and driedr There are obtained 52 parts of an orange powder which dissolves in hot water with a red-orange coloration. The dyestuif dyes wool violet tints by the single bath process'in the presence of an agent yielding chromium.

Example 15 100 parts of thoroughly wetted wool are entered at 60 G. into a dyebath which contains in 4000 parts of water 1.5 parts of dyestuff obtainable as described in Example 4, 2.5 parts of ammonium sulfate, 2.5 parts of sodium chromate and also 20 parts of Glauber salt. The temperature is raised to the boil in the course of 30 minutes, and dyeing is carried on for 2 hours at the boil. The goods are then rinsed and dried. The, wool is dyed a pure bluish-red tint:

What Weclaim i's:, i i J 1. A monoazodyestuifv which corresponds to the formula wherein the -O atoms attached to R1 and R2 are in positions adjacent to the N=N-= group,

R represents a member selected fromrthegroup consisting of mononuclear radicals of the benzene v2. A. monoazo dyestuff which corresponds to:

wherein the-O- atoms attached to R1 and R2 are in positions adjacent to the -N=N- group;

R1 represents a binuolear radical of the naphthalene series, and R2 represents a binuolear radical.

of the naphthalene series, and wherein the -R1-N=NR2 group bears a single sulfonic acid group as the sole solubility-imparting group. 4. A monoazo dyestufi which corresponds to the formula Ra-CO-O NR4 i-N=N-C o=N (5H.

m which the R3 co' o-- group is in a position adjacent to the N=N--'g'rou'p, R1 represents a binuclear radical of the naphthalene series, and each of R3 and R4 represents a mononuclear radical of the benzene series, and wherein the /AINR4 -R1- N=NC C=N as group bears a single sulfonic acid group as the sole solubility-imparting group. 7

5. A monoazo dyestuff which corresponds to the formula group is in a position adjacent to the N=N- group, and each of R1 and R4 represents a monoin which the nuclear radical of the benzene series, and wherein 13 group bears a single sulfonic acid group as the sole solubility-imparting group.

6. A monoazo dyestufl which corresponds to the formula wherein the -O atoms attached to R1 and R2 are in positions adjacent to the -N=N group, each of R1 and R3 represents a mononuclear radical of the benzene series, and R2 represents a binuclear radical of the naphthalene series, and wherein the --R1-N=NRzgroup bears a single sulfonic acid group as the sole solubilityimparting group.

7. A monoazo dyestuil! which corresponds to the formula i-N=NC c= $3, in which the RaCO-O- group is in a position adjacent to the --N=N- group, each 01' R1, R3

and R4 represents a mononuclear radical of the benzene series, and the group bears a single sulfonic acid group as the sole solubility-imparting group.

9. A monoazo dyestuff which corresponds to the formula in which the group is in a position adjacent to the --N=N-- group, R1 represents a binuclear radical of the naphthalene series, and R; represents a mononuclear radical of the benzene series, and wherein the JJN-Ra R1-N=NO group bears a single sulfonic acid group as the sole solubility-imparting group.

10. A monoazo dyestufl' of the formula 11. The monoazo dyestufi of the formula SOaH 12. The monoazo ,dyestufi of the formula SOaH HOG 13. The monoazo dyestuif of the formula FRIEDRICH FELIX. ALPI-IONSE HECKENDORN. WILLY WIDMER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,728,998 Krzikalla Sept. 24, 1929 1,824,914 Mirocourt Sept. 29, 1931 1,844,397 Kammerer et al. Feb. 9, 1932 2,095,600 Graenacher et a1. Oct. 12, 1937 2,120,741 Graenacher et al. June 14, 1938 2,170,262 Graenacher et al. Aug. 22, 1939 2,199,048 Graenacher et al. Apr. 30, 1940 2,237,483 Graenacher et a1. Apr. 8, 1941 2,249,956 Heyna July 22, 1941 2,274,544 Gubelmann Feb. 24, 1942 2,276,187 Graenacher et al. Mar. 10, 1942 FOREIGN PATENTS Number Country Date 510,091 Great Britain July 216, 1939 

9. A MONOAZO DYESTUFF WHICH CORRESPONDS TO THE FORMULA 